Understanding the In-Reactor Performance of Advanced Ceramic Cladding Materials

了解先进陶瓷熔覆材料的反应堆内性能

基本信息

批准号：
EP/M018814/1
负责人：
Timothy Abram
金额：
$ 31.17万
依托单位：
University of Manchester
依托单位国家：
英国
项目类别：
Research Grant
财政年份：
2015
资助国家：
英国
起止时间：
2015 至无数据
项目状态：
已结题

来源：
https://gtr.ukri.org/projects?ref=EP%2FM018814%2F1
关键词：
Understanding Reactor Performance Advanced Ceramic

项目摘要

Accident Tolerant Fuels (ATF) are fuel designs typically intended for use in Light Water Reactors (LWRs), which comprise around 90% of the world's nuclear generating capacity. They offer significantly improved high temperature capability, due largely to the adoption of novel cladding materials, notably ceramic cladding. International fuel vendors are interested in commercialising ATF for both existing and new LWRs, but only after the gaps in technology readiness have been addressed. The aim of the research is therefore to establish the satisfactory performance of advanced ceramic cladding materials that are capable of surviving to temperatures typical of those encountered during severe accident conditions - typically around 1700 deg C. This is achieved by replacing the traditional zirconium-alloy fuel cladding with a composite ceramic cladding that is capable of surviving much higher temperatures. This would provide a very significant increase in safety compared with existing fuels, and hence provide a competitive advantage to UK fuel manufacturers. The work will focus on the performance of joined and bonded SiC-SiC composite cladding under conditions representative of those found in nuclear reactor cores.Silicon carbide has been shown to be stable under irradiation, and has very high temperature capabilities, but it has two major difficulties.1. The cladding must provide a gas-tight tube capable of accommodating the fuel pellets and retaining the gaseous fission products. This requires the sealing of the ends of the tube with a high-integrity joint. However, SiC cannot be welded, and previous attempts to produce mechanical and glued joints have failed. 2. Being a ceramic, SiC has very low fracture toughness, and it must be maintained in compression to provide sufficient mechanical strength. This can be achieved by winding the hollow SiC tube with SiC fibres that keep the tube in compression. However, a suitable means must be found of bonding the fibres to the underlying tube.Recent work at Manchester has identified two promising solutions to these difficulties: the use of laser-induced ceramic brazing to produce a gas-tight seal; and the use of Selective Area Laser Deposition (SALD) to produce a deposit of SiC that can act as a bond between SiC fibres and the underlying tube. These techniques have been demonstrated at laboratory scales, but the braze and bond materials have not been demonstrated under conditions representative of in-reactor service. The principal objectives of the work are therefore to demonstrate that the brazed joints and bonded fibres are capable of surviving under in-reactor conditions.

事故耐受燃料（ATF）是通常用于轻水反应堆（LWR）的燃料设计，占世界核发电能力的90％。它们提供的高温能力可显着提高，这主要是由于采用了新型的覆层材料，尤其是陶瓷覆层。国际燃料供应商对现有和新LWR的ATF商业化感兴趣，但仅在解决了技术准备差距之后。因此，该研究的目的是建立能够生存到在严重事故情况下遇到的典型温度的先进陶瓷覆层材料的令人满意的性能 - 通常在1700度左右。与现有燃料相比，这将提供安全性的大幅度提高，因此为英国燃料制造商提供了竞争优势。这项工作将集中于在代表核反应堆核心的条件下连接和粘合的SIC-SIC复合层覆层的性能。SiliconCarbide已显示在辐照下是稳定的，并且具有很高的温度能力，但它具有两个主要困难。1。覆层必须提供能够容纳燃料颗粒并保留气态裂变产物的气密管。这需要用高融合接头密封管的末端。但是，SIC无法焊接，并且先前生产机械和胶接头的尝试失败了。 2。作为一种陶瓷，SIC具有非常低的断裂韧性，并且必须保持压缩以提供足够的机械强度。这可以通过将空心的SIC管与SIC纤维缠绕，以使管保持压缩。但是，必须找到将纤维粘结到基础管的合适方法。曼彻斯特的果实工作已经确定了这些困难的两种有希望的解决方案：使用激光诱导的陶瓷悬挂式悬挂式陶瓷来产生气密密封；以及使用选择性区域激光沉积（SALD）产生的SIC沉积物，该沉积物可以用作SIC纤维和下层管之间的键。这些技术已在实验室尺度上得到证明，但是在代表反应器内服务的条件下，铜盘和键材料尚未得到证明。因此，这项工作的主要目标是证明悬挂的关节和粘合纤维能够在反应后条件下生存。